A synthetic mechano-growth factor E peptide promotes rat tenocyte migration by lessening cell stiffness and increasing F-actin formation via the FAK-ERK1/2 signaling pathway

Cell stiffness determined by atomic force microscopy and its correlation with cell motility

“…Although some studies agreed with the conclusion that cells with higher motility are softer [8,10,[16][17][18], higher Young's moduli were found in cells with enhanced motility in some studies [20,21,23,24], which is opposite to the conclusion drawn from the comparison of the primary tissue-derived normal and cancerous cells. However, it should be kept in mind that unlike the intrinsic differences in the cancerous cell lines and their counterparts, either treatment with pharmacological agents or genetic modification cannot lead to an intrinsic change in cells but only a series of alternations in gene expression, signaling transduction, cytoskeleton reorganization, and mechanical properties.…”

“…A large difference exists between the studies that assessed the stiffness of cells with modified motility through pharmacological treatment or genetic modification, and cells with higher motility were demonstrated to be softer [8][9][10][16][17][18][19], stiffer [20][21][22][23][24] or unaltered [15] in different studies. Additionally, the values of Young's modulus of the same cell line vary greatly between different investigations [16,25,26], suggesting a great influence of methodological issues on the data obtained by AFM, which will be discussed in the next section.…”

“…However, it should be kept in mind that unlike the intrinsic differences in the cancerous cell lines and their counterparts, either treatment with pharmacological agents or genetic modification cannot lead to an intrinsic change in cells but only a series of alternations in gene expression, signaling transduction, cytoskeleton reorganization, and mechanical properties. As a crucial engine of cell movement, actin filaments need to reorganize into a variety of architectures to allow cell deformation and migration [27,52], and obvious lamellipodium [8], cortical actin filaments [17] and stress fibers [8,16,20,21,23,24] were observed in cells with pharmacologically or genetically enhanced motility. The polymerization of cortical actin filaments and stress fibers, and especially the stress fibers, greatly contributes to the stiffness of cells and leads to an increase in the AFM-determined Young's moduli over the nuclear region [28][29][30][31].…”

“…Additionally, cell stiffness was also found to be associated with the migration capability of non-cancer cells, including mesenchymal stem cells [7], tenocytes [8], embryonic fibroblasts [9] and epithelial cells [10,11].…”

Conditioned medium from mesenchymal stem cells enhances the migration of hepatoma cells through CXCR4 up-regulation and F-actin remodeling

“…Interestingly, we found that an increase in F-actin formation is accompanied with a lessening in cell stiffness. Our previous study showed that the mechano growth factor promotes rat tenocyte migration by lessening cell stiffness and increasing F-actin formation (Zhang et al 2014). Based on these findings, we speculate that MSC-CM may lessen the nuclear stiffness, which plays an important role in determining the superimposed Young's modulus of CBRH-7919 cells.…”